Well, from a technical standpoint, isn't there some common plumbing? Both need a water supply, both need a drain connection. Eliminate one and sure you've eliminated half the plumbing, but you still have the same maintenance issues, just not as many.
From a human standpoint, I can't think of anything a sink in your room can be used for, that the sink in the public bathroom can't. Maybe you could make the argument of people washing their hands headed to the diner without having to wait for the public bathroom, but it's thin, frankly. Then there's the potable water angle, but do these sinks even have a dispenser of potable water?